Hello everyone! First time poster... long time reader... love Zen-Cart :)

Background:

I am trying to apply quantity discounts in a way that I haven't seen thus far. Each product has a discounted price based on quantity purchased. This is easy to do. But here is the twist... I want the discount price for each item to be used if the quantity of the CART as a whole is 1, 2, 3, etc... and not necessarily the item quantity. The resulting discount would NOT be a percentage or fixed dollar amount off. It would be the predetermined price as shown below.


Example:

ProductA
Qty 1 => $100/EA
Qty 2 => $90/EA
Qty 3 => $80/EA
Qty 4 => $70/EA

ProductB
Qty 1 => $50/EA
Qty 2 => $45/EA
Qty 3 => $40/EA
Qty 4 => $30/EA

ProductC
Qty 1 => $5/EA
Qty 2 => $4/EA
Qty 3 => $3/EA
Qty 4 => $1/EA


Cart -
1 ProductA => $70
2 ProductB => $60 (2*$30)
1 ProductC => $1
TOTAL = $131.00

As we can see, I want to use the 'Qty 4' price for EACH item to be used as there are 4 items in the cart.

I have looked into swguy's fantastic Quantity Discount mod, but I don't believe it supports this. What I'm looking for is somewhat of a hybrid between his and the bulit in quantity discount feature.

Any help or guidance in this matter would greatly appreciated!

I'm using Zen-Cart 1.3.8a and PHP 5.2.11

Thanks!